This is a very interesting and concerning situation. At first, I thought your patient was undergoing a type A dialyzer reaction. However upon re-reading your synopsis I believe the remaining chlorine disinfectant is causing the acute hemolysis --> sudden anemia.

To distinguish between these 2 entities, we need to know if other patients, using the same type of dialyzer, have also developed sudden anemia. If so, this would suggest a system-wide problem, such as improper removal of chlorine disinfectant.

At our center, we do not reuse our dialyzers. Therefore, we have very limited experience in using a disinfectant such as chlorine. I cannot comment on what your disinfectant procedure should be.